source/texk/kpathsea/cnf-to-paths.awk

   1 # $Id: cnf-to-paths.awk 23442 2011-08-07 22:50:24Z karl $
   2 # cnf-to-paths.awk - convert texmf.cnf assignments to paths.h #define's.
   3 # Public domain.  Originally written 2011, Karl Berry.
   4
   5 # We assume comments have been stripped.
   6 #
   7 # we only care about definitions with a valid C identifier (e.g.,
   8 # TEXINPUTS, not TEXINPUTS.latex), that is, lines that look like this:
   9 #   <name> = <value>
  10 # (whitespace around the = is optional)
  11 #
  12 /^[ \t]*[A-Z0-9_]+[ \t]*=/ {
  13   # On these lines, we distinguish three cases:
  14   #
  15   # 1) definitions referring to SELFAUTO*, which we want to keep.  In
  16   # particular, this is how the compile-time TEXMFCNF gets defined and
  17   # thus how texmf.cnf gets found.
  18   #
  19   # 2) definitions starting with a /, which we also want to keep.  Here
  20   # we assume a distro maintainer has changed a variable, e.g.,
  21   # TEXMFMAIN=/usr/share/texmf, so keep it.  (This also preserves the
  22   # default values for OSFONTDIR and TRFONTS, but that's ok.)
  23   #
  24   # 3) anything else, which we want to convert to a constant /nonesuch.
  25   # That way, the binaries don't get changed just because we change
  26   # definitions in texmf.cnf.
  27   #
  28   # The definition of DEFAULT_TEXMF (and other variables)
  29   # that winds up in the final paths.h will not be used.
  30
  31   # Extract the identifier and the value from the line.  Since
  32   # gawk's subexpression matching is an extension, do it with copies.
  33   ident = $0;
  34   sub(/^[ \t]*/, "", ident);
  35   sub(/[ \t]*=.*/, "", ident);
  36
  37   val = $0;
  38   sub(/^.*=[ \t]*/, "", val);
  39   sub(/[ \t]*$/, "", val);
  40   #print "got ident", ident, "and val", val >"/dev/stderr";
  41
  42   if (val ~ /\$SELFAUTO/) {
  43     # Replace all semicolons with colons in the SELFAUTO paths we're keeping.
  44     # (The path-splitting code should be changed to understand both.)
  45     gsub(/;/, ":", val);
  46   } else if (val ~ /^\//) {
  47     # If the value starts with /, presume we're compiling with changes
  48     # made for a distro, and keep it.  Likewise switch to :.
  49     gsub(/;/, ":", val);
  50   } else {
  51     val = "/nonesuch";
  52   }
  53
  54   print "#ifndef DEFAULT_" ident;
  55   print "#define DEFAULT_" ident " \"" val "\"";
  56   print "#endif";
  57   print "";
  58 }